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CVE-2026-8159 (GCVE-0-2026-8159)

Vulnerability from cvelistv5 – Published: 2026-05-12 08:35 – Updated: 2026-05-12 12:33
VLAI
Title
multiparty vulnerable to ReDoS via filename parsing
Summary
multiparty@4.2.3 and lower versions are vulnerable to denial of service via regular expression backtracking in the Content-Disposition filename parameter parser. A crafted multipart upload with a long header value can cause regex matching to take seconds, blocking the event loop. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: limiting upload sizes at the proxy or gateway layer reduces but does not eliminate the attack surface, since a small header of around 8 KB is sufficient to trigger the vulnerable backtracking. Upgrade to multiparty@4.3.0 or higher.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-12 12:33 UTC
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
References
Impacted products
Vendor Product Version CPE status
multiparty multiparty Affected: 0 , ≤ 4.2.3 (semver)
Unaffected: 4.3.0 (semver)
guessed Create a notification for this product.
Credits
aszx87410 Blake Embrey Ulises Gascón
Show details on NVD website
To clipboard 

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